Question2: When parking a car in a downtown parking lot, drivers pay according to the number of hours or fraction thereof. The probability distribution of the number of hours cars are parked is given below

X 1 2 3 4 5 6 7 8
f(X) 0.30 0.24 0.17 0.10 0.08 0.05 0.04 0.02

a. Calculate the mean and standard deviation of the number of hours cars are parked in the lot.
b. The cost of parking cars $2.5 per hour. Calculate the mean and standard deviation of the amount of the revenue each car generates.